In November 2011, ruxolitinib (Jakafi; Incyte/Novartis), a small-molecule inhibitor of Janus kinases, was approved by the US Food and Drug Administration for the treatment of patients with intermediate or high-risk myelofibrosis, including primary myelofibrosis, post-polycythaemia vera myelofibrosis and post-essential thrombocythaemia myelofibrosis.